The surface energy of a material refers to the energy per unit area of the surface of the material. High surface energy materials such as metal and glass have strong adsorption capacity and can better contact with liquid molecules to form a strong adhesion. Low surface energy materials such as polyethylene (PE) and polypropylene (PP) have poor adhesion performance due to the weak attraction between their surface molecules and are difficult to contact with liquid molecules.
In the application of self-adhesive labels, the surface energy of the material directly affects the adhesion of the ink. High surface energy materials can ensure that the ink forms a uniform and strong adhesion layer on its surface, thereby improving the printing quality and wear resistance.
Dyne pens are commonly used tools to measure the surface energy of materials. By drawing a line on the surface of the material and observing the changes in the line, the surface energy of the material can be determined.
If you want to improve the surface energy of the material, corona treatment is an effective method. Corona treatment uses high-frequency and high-voltage current to discharge on the surface of the material. This discharge will generate a large number of high-energy ions and free radicals, causing the molecular structure of the material surface to change, thereby increasing its surface energy and increasing the ink binding force.
This method is particularly suitable for low surface energy label materials such as PE and PP. For customers who do not have corona treatment equipment, they can choose coated PE materials. This type of material has been surface treated before leaving the factory, has good ink adhesion, and can adapt to harsh application environments.For more questions about label materials, welcome contact SINOPACK